While many absorbent adhesive dressings are known, there is still room for improvement in moving closer to meeting the various desired properties of the ideal dressing for managing ulcer and burn wounds. Such wounds tend to exude much wound fluid exudate. What has been long sought, which the present invention offers, is a dressing which is especially absorbent, occlusive and adhesive, while providing an improved wound healing environment, and which manages exudate with the convenience of an adhesive facing so that no tape is needed to hold it in place.
Existing hydrocolloid absorbent adhesive dressings dissolve in the presence of wound fluid unless changed frequently, leaving a wound bed which must be cleaned before application of a fresh dressing. The particular adhesive used in the dressings of the present invention does not dissolve, but actually provides a relatively occlusive interface with the wound, while permitting exudate to pass gradually through it into the dressing's absorbent middle layer leaving the wound clean of both wound exudate and adhesive upon removal of the dressing from the wound. The adhesive serves the further function of being impervious to bacteria and other potential wound contaminants from exogeneous sources, i.e., those outside of the wound itself. Since the dressing is topped with an occlusive film outer layer e.g. polyethylene, it is impervious to bacteria and other potential wound contaminants. The preferred dressing manages wound fluid from a highly exudative wound for up to 3 days without exudate accumulation in the wound bed, while providing a moist environment which fosters repair.
Burns and ulcers are often debrided by use of a debriding enzyme applied thereto. Existing dressings which are occlusive enough to provide an optimal environment for repair permit puddling of exudate. When enzyme is applied under such existing dressings, the accumulated pools of exudate can wash away the debriding enzyme if the exudate escapes from under the dressing. In the embodiment of this invention wherein the debriding enzyme is applied to the face of the dressing, this is no longer a problem, because exudate does not Pool or escape from beneath the dressing. Because the adhesive layer uniquely slows exudate absorption, the enzyme on the adhesive face acts to dissolve necrotic tissue in the wound bed even though some exudate is constantly being absorbed by the dressing.